Switch operated by float actuating mechanism



Jan. 2, 1951 c. GAHAGAN SWITCH OPERATED BY FLOAT ACTUATING MECHANISMFiled Nov. 2, 1949 A W 0 I Il 0 Il W I `\.\\\\\x m n eA 0 1 0 l W W v 23 g 9 .PM l F 5 O 5 6 7 2 2 9 3 2 1/ 2 2 w f w 1f Il .7 y f .f 2 I. ,Ifm /H/f ln .md .ig LE LEV F l m Ew EN Lm LM Hf wf Wa@ :inventor FL UID@ENI/TY EJPONJ/VE CLOY' GAHAGAN Gttorneg Patented Jan. 2, 1951 UNITEDSTATES PATENT OFFICE SWITCH OPERATED BY FLOAT ACTUATING MECHANISM CloyGahagan, Darlington, Md.

Application November?, 1949, Serial No. 125,084

This invention relates to an alarm system for association with a vesselcontaining a fluid, and

is particularly directed to mechanism for detecting and indfcatingvariations in total volume of For satisfactory operation of turbineshaving bearings of this character, in which the turbine rotor operatesat relatively high speed about a vertical axis and its upper mainbearing therefore receives thrust stresses of large magnitude, it isessential not only that the quantity of oil in the tank be kept fairlyconstant at level sufficient to keep the bearing surfaces submerged andto in'A sure this that a signal be given in the event of materialincrease or 'decrease of the total oil` volume, but also that theoperatives in charge be immediately apprised of contamination of the oilby leakage thereinto of water from the cooling- 7 Claims. (Cl. ZOU-84)coils or elsewhere so that proper remedial meas-A ures can be adoptedbefore serious damage to the equipment results. 1

Liquid level indicators including to actuate visual and/or audiblesignals have heretofore been suggested for indicating changes floatsadapted in the volume of lubricant in the tanks surrounding the bearingsof such turbines, but as far as I am aware these have been responsiveonly to changes in total volume of liquid and incapable ofdiscriminatingbetween lubricant fluid anda contaminant such as water, with the resultthat no signal or alarm is given thereby should lubricantescape and'water enter the reservoir in corresponding quantity and so maintain asubstantially constant total fluid volume therein;

hence should such a condition occur material in Jury vto the bearingsmay* result from the entry of water without appreciable accompanyingchange in volume, and hence without its presence being noted before theequipment has been damaged.

It is therefore a principal object of the inveni tion to providemechanism for promptly energizing an alarm'or-other vsuitalzlle lsignalwhen theltotal fluid volume ina fluid containing tank'or`r reservoirbecomes greater or less than valueswithin a predetermined range andalso, substantially independently of the volume of said fluid,

vshould a contaminating fluid of different specific gravity be admittedaccidentally to the tank as by leakage from a cooling coil, conduit orother SOllICe.

A further object is to provide in combination :with means for indicatingwhen the quantity of oil in a turbine bearing lubricating tank or thelike exceeds or is exceeded by the limits of a given range, meansoperative to promptly actuate an alarm signal should water or othernon-lubricating fluid of higher specific gravity than the oil enter thetank and thereby apprise the operatives of the existence of a conditionnot readily observable but which would result in injury to the turbinebearings if the turbine were kept in operation.

Other objects, purposes and advantages of the invention will hereaftermore fully appear or will be understood from the following descriptionof and the accompanying drawing illustrating one embodiment of itadapted for use in association with the lubricant containing housingsurrounding the upper main bearing of a hydroelectricgenerator turbine.

In the said drawing,

Fig. 1 is a front elevation, partly in section, of the alarm actuatingmechanism;

Fig. 2 is a rfragmentary enlarged front elevation showing the partsthereof directly associated with the alarm energizing circuits; Fig. 3isa similarly enlarged fragmentary section on the line 3-3 in Fig. 2,and

Fig. 4 is a fragmentary enlarged detail in side elevation of a portionof Fig. 1.

Referring now more particularly to the drawing, the mechanismillustrated therein comprises a tubular casing l adapted to be installedrand supported in upright position adjacent a turbine bearing housing orthe like (not shown) and provided at its ends with caps 2, 3. Thiscasing'Y is connected 'through a conduit 4 with the lower part or bottomof the lubricant reservoir of the housing or preferably with the drainpipe extending .downwardly therefrom whereby when the conduit is openalevel of fluid in the casing cor responding to that in the reservoir ismaintained by hydrostatic pressure in the latter. Within the casing land extending axially thereof is x' edly lsupported a guide rod 5 onwhich is slidably mounted an elongated sleeve 6 carrying at its lowerend a sealed hollow bulb l either evacuated or containing air. Abovethis bulb at a convenient point on sleeve 5 is fixed a collar 8supporting on the sleeve a plurality of annular Weights 9 of which anysuitable number may be employed as will hereafter appear; preferablythese weights are so designed they may be applied to or removed from thesleeve at will so as to increase or decrease their total mass. Restingon the upper end ofthe sleeve :and movable with S of any well known typeresponsive to movement of mag-netv I4, the switch being suitablyvsupported upon the yoke adjacent the path of the magnet' and arranged tobreak or make a circuit to there.;A byV operate any desired type ofalarm device adapted to give an audible, a visual, or a graphicindication whereby vertical movement of sleeve 6 upwardly beyond apredetermined limit is yreeect'ed in a perceptible signal as will behereafter more fully explained.

`Surrounding and freely slidable on sleeveis a somewhatshorteroutersleeve I5, supportingl at its upper end a bracket I6carrying a pin Il similarly slidable in aslot'le in the other arm ofyoke 'i3 and supporting' another switch actuet. ing element such asmagnet I9 foractuating in like'manner a switch Sl, or other e'iuivale'ntcr-` cuit controlling means, connected through suits able wiring with asecond alarm device (not shownl which desirably is adapted to give adif-` ferent kind of alarm or signal than the dev-ice actuated fromswitch S so'as to differentiate therefrom.

A4 hollow annular 'cat 20 is secured to outer sleevev l5 ata suitablepoint anais sealed to coneV fine a. vacuum erair wherebyy the floatysupports sleeve I5 at a level such vas to maintain switch' S' inactivewhen the iluid in casing vI and-hence in the reservoir with which itVis-connected is vat the proper operating level.

Another annular hollow neat 25 also surrounds sleeve t5 but isfreelyslidabie thereon and ner'.V mally rests upon'float -20,`the.latterbeing made with buovancy sufficient, to'support oat. 25 as Well'as sleeve' I5', and' aslot 2S in sleeve I5 Firef-` vides a guide for anin 2T extending radially from a vertically adju-stable. collar 2i!(Fig. 4). on the inner sleeve 6 and overlying' slid'able oat 25 foi`engagement therewith when the flcat'rises on the outer sleeve for thedistance,v 'determined bythe adiusted position ofthe collar.

Bracket It supported by the upper end 'of outer sleeve I5 is adapted toengagea, preferably adjustable, stop 3l).l carriedby Ayoke'lii near itsupper end after it has been lifted by oat 2t to a'predetermined heightcorresponding to norY` mal lubricant level, and it Vis only after suchen gagement of this bracket with the stop'that float 25 can riseindividually on ythe sleeve and so away from ileat 210 to yengage'pin2-1'. After suehenfk gagement however, further upward travel o-f iicatV3i also carried bythe yoke.V

At its lower end the casing is provided with a drain cock 32 to allowthe fluid in it to be bled away when desired, and valves 33, 3drespectively in conddit 4 and the drain cock line allow a body of uid inthe casing to be held static therein for testing or the like, while theyoke i3 and associated parts are preferably enclosed in a removable dustcover or housing 35.

The alarm actuating mechanism herein described When initially installedis provided with weights 9 of sufficient mass to hold sleeve 5 and its'`attached parts floating in lubricant in the casing through the buoyancyof bulb l and at a level insufcient to actuate switch S when thelubricant level is such as to hold iioat 2B and outer vsleeve i5 at alevel higher than that at Awhich switch S' is actuated. So long as thislevel of lubricant is maintained switches S and S therefore remaininactive and no alarm is given.

Assuming now, however, that lubricant escapes from the bathe; the levelin casing l consequentlyfalls and float 2B and hence outer sleeve i andmagnet I9 therefore descend, actuating switch S to break or make thealarm circuit andv soA signal that the total lubricant. volume in thebath is insuflicient. Y

If additional lubricant now be supplied float,- 20 is of coursecorrespondingly raised to the point,

at. which stop 3l] is engaged by its bracket which of course correspondswith the normal level ci lubricant in the reservoir but if still more issup'-v plied, thus creating an excess over the. proper amount oat 25rises free of float 2t and after engaging pin 2 ultimately lifts innersleeve sufficiently to actuate switch S and so Warn4 through the alarmsignal controlled thereby that too much lubricant has been added.

These operations, it will be understood. are results solely ofhydrostatic pressure and give indications only oi?,v the total fluidvolume in the tank whether this be oil alone or cil contaminated withwater. Assuming however that, with the volume of oil remainingsubstantially constant at the de sired value, a little water leaks into,it from the.' lcooling coils or elsewhere; being heavier than the 'ioil-'the water promptlypasses to the bottom of the reservoir and 'thencethrough conduit into cas, ing I. Ii `of sufficient volume to force theoil out of conduit. 4 the water may raise the oil level in casing I'above. that in the bearing bath and by hydrostatic pressure alone, liftfloat disc. 25 suffi cientlv to give-'an alarm before anyappreciablequantity of it has actually entered casing I. But f should it seepvrelatively gradually into the lat,-

.ter reliance solely upon the. increased total fluid volume in thesystem would result in introducition` of a. deleterious quantity ofwater before alarm were given. Ity will be apparent however that inaccordance with mv invention when water in any manner enters the casingI in apa Conseouentlv', after the admission oi"v very little water intothe casing the switch S is actuated to give an alarm even before theincrease in the total volume of oil and water in the system loe-V comessuflicient to lift the tube 6 through the medium voi oat`25.Furthermore, even if water passes into the'syste'm contemporaneouslywith the escape of oil therefrom' at the same -rate,-

for switch S to be actuated, a conclusion 'which can, vof course, beverified by opening the drain cock 32 at the bottom of the casingandgfinspect'- ing the outflow, since water canv'readlli'yf` be disvtinguished from lubricant even vif their color characteristics shouldbethe same.

'The apparatus requires no resetting after rectiiication of thecondition resulting'inan alarm,

since any water in the casing is normally drained therefrom inconnection with its removal fromv the main lubricant bath, and aftergaproper quantity of water-free lubricant is re-introduced to thereservoir` the mechanism is restored autom'atically to its normal,condition and so ready to give an appropriate alarm uponsubsequentmaterial change in the depth of the lubricant bath or itscontamination by water.

While I have herein illustrated and described apreferred embodiment ofthe invention as employed in association with a bearing lubricantbath ofa specic and well-known type, it will be understood it may be utilizedwith equally good results in other associations and that changes andmodifications in the form, construction, ar rangement 'and relationshipof the several parts 6 normal level of the fluid therein, fluid levelr.e.` sponsive means for actuating one of the elements', during loweringof uid level in: the casing, fluid density responsive means foractuatingthe vother j' element on. an increase in the density of. the" fluid inthe casing, means for limiting the upward travel of the first fluidresponsive means on increase of the iluid level above a predeterminedpoint and a second iluid level responsive meansA normally `carried bythe first such means operative on increase in said iluid level abovesaid point to actuate the density responsive means independently of thedensity of the fluid to thereby actuate the second element in responseto said increased fluid level.

4. Anv alarm actuating device comprising a casing adapted forinstallation in substantially' vertical position, a vguide rod'extendinglongi` tudinally of ythe casing, a bulband sleeve assembly sli'dableonthe' rod vadapted to float at a predetermined -level in' a liquid ofgiven specific gravity contained inthe casing, a switch supported on thecasing, means interposed between said assembly and switch operative toactuate the latter on upward movement of sa'd assem- `j bly induced byintroduction to the casing of another liquid of higher specific gravity,an outer v sleeve. slidable on the rst sleeve, a float fixed willreadily occur to those skilled inthe art and may be made if desiredwithout departing from the spirit and scope of the invention as definedin the appended claims. j Y

Having thus described my invention, I claim and desire to protect byLetters Patent of the United States: .v

l. Alarm switch actuatng mechanism comprising a pair of reciprocalswitch actuating elements, fluid density responsive `me'a'ns foractuating one of the elements, fluid .level responsive means foractuating the otherlellement and second iluid level responsive meansnormally seated on the rst such means operative to actuate the iiuiddensity responsive "jrneans independently of the fluid density when saidsecond fluid level responsive means are raised from said first duidlevel responsive means.

2. An alarm actuating device comprising a pair of independently operablecircuit control switches, reciprocal elements for actuating saidswitches, a fluid container, fluid supported means disposed therein formoving one oilsaid elements in a direction to actuate the.-eorresponding switch in response to a loweringoflthe normal fluidlevel in the container, fluid density responsive means for actuating theother element in responseto displacement of a portion of said iluid by afluid of greater dens and means normally seated on said uid l,` lresponsive means operative to actuate the second element independentlyof the iluid density when the fluid level rises above normal.

3. An alarm actuating deviceg-.comprising a casing adapted to contain afluidatWO vertically reciprocal switch actuating elements disposedadjacent the upper end of the casing above the thereto adapted to floaton the fluid in the casing, a second switch supported on the casng,means' interposed between said-second switch and said float operative toactuate the'switch when said 'iloat .falls below a predetermined pointon*` diminution of the Atotal volume of ilu-'d in the casing, a secondflo-at surrounding the outer sleeve and normally resting on the firstfloat,

means carried by said assembly engageable bythe second float to liftsaid assembly and actuate the rst switch when the second iloat risesabove a predetermined point 1'ndependently of 'the first float as aresult of increase in the level of 'said fluid, and means operative tolimit the upward movement of the outer sleeve and rst float prior to theindependent upward movement of the second float.

5. An alarm actuating device comprising a casing adapted forinstallation in substantially vertical position, a guide rod extendinglongitudinally of the casing, a bulb and sleeve assembly slidable on therod adapted to float at a predetermined level in a liquid of givenspecic gravity contained in the casing. means associated with saidassembly for adjustab'y varying said level, a switch supported on thecasing, means interposed between said assembly and switch operative toactuate the latter on upward movement of said assembly induced bvintroduction to the casing of another liquid of higher f specificgravity, an outer sleeve slidable on the iirst sleeve, a float xedthereto adapted to float on the fluid in the casing, a second switchsupported on the casing, means interposed between said seco-nd switchand said float operative to actuate the switch when said float fallsbelow a predetermined point on diminution of the total volume of fluidin the casing, a second iloat surroundingr the outer sleeve and normallyresting on the first float, means carried by the first sleeve engageableby the second float to lift said assembly and actuate the first switchwhen the second lloat rises above a predetermined point independently ofthe first float as a result of increase in the level of said fluid, andmeans op erative to limit the upward movement of the masons-afi pendentupv/'ard movement of the 'secondY float.'v

, `6. `v An"alarnr-actuating device comprising` a. :ease 't ing` adaptedforinstallation in a substantially: vertical position, aEguidelrod-extending Vlongi tudinaily of the casing, apair of switchesYmenanted adjacent the top of thelcasing, a sleeve'and bulb'assemblyslidable on .said rod adapted. toi. float at a predetermined level intheoasingwhen the latter eontansuid of given specific gravity,-means-interposed betweenY said sleeve and onez of said switenesforaetuatingl the'latter Wheng said-assembly rises asa result' ofintroductionv te the casing yof uid of higher'specie gravity,

Lan o-uter sleeve slidable on the-flrstsleeve, 'av

floatv xed to thefseccimisleeve.adaptedizo-float limitposition Vas theresuit oilan increase of 'the normal level of said' fluid.

7. An alarm Ydevice comprising aoasingadapted forY installation ina'substantially martina-ipo@ sitionand having a-rluid inlet at itsrlower end,

a -guide rod :extending,longitudinally of the `easing,a pair of switchesmounted adjaeent the v upper-end 'of the casing, an inner sleeve"slidable' on-the roell havinga oat bulb fixed at :its lower' endYadapted"to support the sleeveat a predeter. mined height vwithrespeet'to the easing -rwhen-l.

disposed inr-a'iliid of givenspeeic gravitystand" ingfa-t a givenrlevel:in the casing, means inter-,fposed'between said sleeve and one of saidswitch*v esl" :forl .actuating :the latter when the bulb risesff.' a'1predetermined 'distance as a vresult of intros-v ductionV :to Vthe'casing-ofu iluid of higher speciile.; gravity, an outer sleevesurrounding the inner- Sleevaa'float'xed tothe outer sleeve, a secondi'loatmovableron the outer sleeve independentlyv of 'ther'st neat-andadapted to normally rest onr the latter;the''first'float supporting thesecond leatlandouter-sleeve at a predetermined'height in'thelcasingWhen'the fluid therein is at the` aore'said Ag'ivenlevel, meansinterposed between i th'e'outer sleeve and the other switch for actu--ating the latter 'When'the outer sleeve and floats" fall"on` reductionof that level, a' stop limiting up: ward movement ofthe'rstloat andouter sleeve? and means carried ley-the inner sleeve extending:Sinto-the -path of' independent `movement ofV the seoondsiiloat forengagement thereby after/the rstoatattains the limit of its upwardmovementand the second iloat continues to rise indes' pend'en'tly uponan' increase in the height of the f-il'uid inthe casing 'above theaforesaid given level whereby to eausev the second float to lift theinner.` sleeve and bulb vassembly and actuate the rst RIFLFERE.NCESACITEDV The VVfollowing'references are of recorclinv thel Number Y 'NameDate` 438,598v Ashton oet. 21,1890; 150665429 Gusan- July 1, 19132,419,942 Brewer May 6, 11947

